The following Specific Aims will be addressed in this Phase 1 proposal: 1) Demonstrate the capability of Liquid Tissue TM protein array methodology to reproducibly perform qualitative and quantitative expression analysis of tumor biomarkers in formalin fixed, paraffin embedded prostate cancer tissue. 2) Demonstrate the capability of Liquid Tissue TM protein array analysis to provide for molecular distinctions between early, moderate, and high Gleason grades of prostate cancers directly from archival formalin fixed prostate cancer tissue. The objective of this proposal is to pioneer novel and innovative technologies for the analysis of protein markers of disease through use of formalin fixed archival tissue leading to improved methodologies and strategies for determining cancer prognosis. Current methods for high throughput protein profiling of forrnalin fixed tissue are limited. This proposal strives to develop the ability to exploit large, extensive, and under-utilized collections of formalin fixed archival tissue for innovative molecular profiling approaches. This will be accomplished by demonstrating utility and piloting the application of Expression Pathology, Inc.'s innovative and patent-pending Liquid Tissue TM methodology for the procurement of solublized protein from formalin fixed tissue and reverse phase Liquid Tissue TM protein arrays for qualitative and quantitative analysis of proteins directly from formalin fixed tissue. The goal of this Phase I proposal is to explore the ability of this novel technology to reproducibly assay for qualitative changes in proteins, such as phosphorylation events, and relative quantitative levels of specific proteins, such as increased expression of tumor markers, in cells obtained from formalin fixed cancer tissue. This proposal could have tar-reaching implications in the prognostic field where decisions based on qualitative and quantitative measure of specific cancer-associated biomarkers in cancer tissue impact patient care. Prostate cancer will provide the model to pilot applications of this novel technological strategy to prognosis. Prostate cancer was chosen because the majority of prostate cancers show moderate grade cancer (Gleason grade 3) and current methodologies to determine prognosis and predict response to therapy of these men are relatively ineffective. The general plan of this proposal is to demonstrate that formalin fixed prostate cancer tissue can be utilized with EPI's Liquid Tissue TM methodology and Liquid Tissue TM protein arrays for qualitative and quantitative analysis of multiple prostate cancer biomarkers, and that this novel strategy can be used to provide for molecular distinction between various stages of prostate cancer which would lead to improvements in the prognosis of moderate grade prostate cancer.